The invention relates to a wrapped yarn spinning machine with several spinning units arranged in a row in side-by-side relationship on at least one machine side, each of these units comprising a delivery device for a sliver; a hollow spindle following in the conveying direction of the sliver, this spindle carrying a binder thread in the form of a spool and being supported in a bearing box and driven with a drive means; and a subsequent take-up device for spun wrapped yarn, wherein the zone of the hollow spindle carrying the binder thread spool is protected by a closed housing, which latter is equipped at each spinning unit with a lid that can be moved out of the way to uncover the hollow spindle.
In a conventional wrapped yarn spinning machine (U.S. Pat. No. 4,226,077), each individual hollow spindle is provided in the region of the binder strand spool with its own enclosure shaped like a cylindrical tank. The hollow spindles are respectively supported within a bearing housing on swivel arm brackets that are pivotable about horizontal axles. The bottom of each enclosure is also supported on a respective one of these swivel arm brackets. Between the enclosures and the bearing housings, each hollow spindle is equipped with a whorl that extends into the bottom of the respective tank-shaped enclosure. The tank-shaped enclosures take care that the zone of the binder thread and especially the balloon of the binder thread, which is being formed, are protected against airborne fibers which can be expected in any spinning shop and are produced, for example, by the delivery device for the wrapped yarn spinning machine proper. The enclosures thus avoid the danger that the fly fibers are caught by the balloon of the binder thread, whereby they could be tangled up as wads or so-called "flags". These "flags" would result before long in breakage of the binder thread since they adhere to the site of largest diameter of the balloon and are not entrained.
The measures taken in the conventional type of construction for protecting the binder strand spools are, however, very expensive and not yet fully satisfactory in their result. Since the whorl of the hollow spindles must be extended through the bottoms of the tank-shaped enclosures to the area of their bearing support on the swivel arm brackets, it is impossible to completely seal the enclosures in this region, for the reason that a relatively large amount of play must be left for tolerance purposes between the whorls and the bottoms. Moreover, a rather complicated and also heavy construction results, inasmuch as the tank-shaped enclosures must be pivoted together with the spindles. Since, in the conventional type of structure, the ingress openings for the hollow spindles are arranged in relatively close proximity to the delivery devices, namely, at a spacing which is smaller than the staple length, the lid of the cylindrical enclosures can only be removed after the hollow spindles have been swiveled out of the way. This requires two manipulations for uncovering the hollow spindles (i.e., first pivoting of the enclosures and, second, opening of the lids), and in this connection, it is also disadvantageous that the binder strand spools can be grasped for exchanging only from the topside of the tanks.
Accordingly, the present invention has as its principal object the construction of a wrapped yarn spinning machine of the type discussed hereinabove so that, with a low expenditure in designing and construction, the binder thread spool is securely protected against fiber fly while, additionally, the accessibility of the hollow spindles and especially of the zone of the binder thread spools, for exchanging the latter, is not impeded. This object has been attained in accordance with preferred embodiments, by combining the enclosures for the plurality of binder thread spools of one machine side into a single housing extending in the longitudinal direction of the machine, this housing being equipped, at each spinning unit, with a lid, arranged on the machine side, that has a height corresponding at least to the height of the sidewall of the box-like housing; by arranging silver feed tubes between the inlet openings of the hollow spindles and the delivery devices; and by sealingly connecting the bearing housings of the hollow spindles with the bottom of the housing, the spindles projecting from the bearing housings in the direction of the take-up devices and being driven in this zone by the drive means.
By the use of a stationary housing as the enclosure, a further objective is achieved in that the parts to be moved for servicing have a lower weight. By employing the sliver feed tubes extending from close proximity to the spindle within the enclosure to near the delivery device, greater constructional freedom is attained, especially regarding the distance of the hollow spindles from the delivery devices, so that accessibility to the binder thread spools is improved, particularly in conjunction with the large-area lid provided. Due to the sealed connection of the bearing housings to the bottom of the housing, a perfect, no-gap seal is also ensured in this region. The provision of the drive unit underneath the bearing housings results in a clear, segmented subdivision, wherein the sector in which spinning technology is performed is separated from the drive-performing area. Additionally, an optically pleasing, compact appearance is obtained for the entire machine.
These and futher objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.